Robustness of Griffiths effects in brain models

Időpont: 
2019. 09. 27. 10:15
Hely: 
Building F, stairway III., seminar room of the Dept. of Theoretical Physics
Előadó: 
Géza Ódor (MFA)

Recent experimental evidence suggests, that our brain operates near criticality, where spatial and temporal correlations diverge, a dynamics, that enhances the brain information-processing capabilities, increasing sensitivity and optimizing the dynamic range. It might be the case that the brain tunes itself near criticality via self-organization, or alternatively, could benefit from the same  properties if sufficient heterogenities (that is disorder) are present to induce an extended semi-critical region, known as Griffiths Phase. In the entire Griffiths Phase, which is an extended control parameter region around the critical point, fluctuations diverge and auto-correlations exhibit fat tailed, power-law behavior. I provide numerical evidence for the robustness of the Griffiths Phase in dynamical threshold model simulations on a large human brain network with N=836733 connected nodes [1,2,3].

 

[1] G. Odor and M. Gastner, Sci. Rep. 6, (2016) 27249.
[2] G. Odor, Phys. Rev. E 94, (2016) 062411.
[3] G. Odor, Phys. Rev. E 99, (2019) 012113.